Surgeon General's Report On Alcohol, Drugs and Health can be found at addiction.surgeongeneral.gov. You may be particularly interested in the Executive Summary [PDF] or the chapter on the Neurobiology of Addiction [PDF].

In 2015, substance use disorders affected 20.8 million Americans—almost 8 percent of the adolescent and adult population. That number is similar to the number of people who suffer from diabetes, and more than 1.5 times the annual prevalence of all cancers combined (14 million). Of the 20.8 million people with a substance use disorder in 2015, 15.7 million were in need of treatment for an alcohol problem in 2015 and nearly 7.7 million needed treatment for an illicit drug problem.

Substance use disorder treatment in the United States remains largely segregated from the rest of health care and serves only a fraction of those in need of treatment. Only about 10 percent of people with a substance use disorder receive any type of specialty treatment. Further, over 40 percent of people with a substance use disorder also have a mental health condition, yet fewer than half (48.0 percent) receive treatment for either disorder.

Treatment is effective. As with other chronic, relapsing medical conditions, treatment can manage the symptoms of substance use disorders and prevent relapse. Rates of relapse following treatment for substance use disorders are comparable to those of other chronic illnesses such as diabetes, asthma, and hypertension. More than 25 million individuals with a previous substance use disorder are in remission and living healthy, productive lives.

For instance, people who first use alcohol before age 15 are four times more likely to become addicted to alcohol at some time in their lives than are those who have their first drink at age 20 or older. Nearly 70 percent of those who try an illicit drug before the age of 13 develop a substance use disorder in the next 7 years, compared with 27 percent of those who first try an illicit drug after the age of 17. Although substance misuse problems can develop later in life, preventing or even just delaying young people from trying substances is important for reducing the likelihood of more serious problems later on.

Many more people now die from alcohol and drug overdoses each year than are killed in automobile accidents. The opioid crisis is fueling this trend with nearly 30,000 people dying due to an overdose on heroin or prescription opioids in 2014. An additional roughly 20,000 people died as a result of an unintentional overdose of alcohol, cocaine, or non-opioid prescription drugs.